A tape carrier package (hereinafter referred to as TCP) made by the TAB or tape automated bonding method has been used broadly in the field of the semiconductor packaging technology, because it enables to maximize the number of pins and also to minimize the pitch of or distance between leads, so as to meet the requirements, due to the recent trend toward higher-level function and higher integration of a semiconductor chip, to increase the number of electrodes, to make the electrode pitch finer, and to make the chip size larger. In the prior art, the electrodes of a TCP have been arranged along two or all four sides on the surface of a semiconductor chip, as described in Japanese Patent Laying-open Publications Nos. 4-22146 and 5-326622. Another Japanese Patent Laying-open Publication No. 63-84039 also discloses a structure for packaging a TCP, in which bumps are formed in the central area on the surface of a semiconductor chip, so that the outer leads of a tape carrier to connect to said bumps are routed inward of the chip, and thus minimizing its mounting area and achieving higher package density. Further, the international publication No. WO91/16656 of this applicant discloses a semiconductor chip in which output electrodes are formed along a longitudinal center line of the rectangular chip.
In most liquid crystal displays, TCPs have been employed to mount driver semiconductor chips for driving a LCD, because a back-light unit can be installed to the display panel very easily and also because TCPs are suitable for automating the mounting process. Here, it is advantageous to configure the driver chips in the form of long and narrow rectangle, and to locate input and output electrodes along the opposite long sides of the rectangular chip respectively, as described in the above Japanese Publication No. 5-326622, in order to shorten the width of a TCP so that the so-called frame portion of a LCD panel is diminished.
While the longitudinal dimension or length of a TCP on which the above-mentioned long and narrow rectangular chip is mounted is generally determined by the number of electrodes and its pitch size of the chip, the lateral dimension or width of the TCP is determined mainly by 1) length of input and output outer leads, 2) length of input and output inner leads, 3) wirings routed on a tape carrier to connect the inner leads and the outer leads, and 4) length of the short side of the chip. FIGS. 10 and 11 show such a TCP as one typical example of the prior art. In the drawings, TCP 1 includes a semiconductor chip 2 as a LCD driver which is positioned in the device hole 4 formed in the center of a tape carrier 3. On the top surface of the chip 2, a number of output electrodes 5 and input electrodes 6 are arranged in one row along the opposed long sides of the chip respectively, and are bonded to inner leads 7, 8 formed to project into the device hole 4. The inner leads connect to outer leads 11, 12 by wirings 9, 10 formed on the surface of the tape carrier 3.
In this example of the prior art, the length of the outer leads 11 and 12 are determined, to some extent, by the conditions of mounting said TCP to a LCD panel and connecting it to an external input circuit, and the length of the inner leads 7 and A are determined partly by the size and pitch etc of said electrodes of the chip 2. Length of the short side of the chip 2 can be usually shortened by improving the degree of integration of the chip so that the chip size is reduced, though there is of course always a physical limitation. Moreover, there is another problem that the chips will become expensive, because machinery necessary for manufacturing such semiconductor chips of higher degree of integration are very expensive and also the manufacturing cost will be increased. Consequently, in order to achieve reduction in the size of a TCP, it is preferred to reduce the mounting area of the semiconductor chip 2 by particularly reducing the wiring area for the output wiring 10 on the surface of the tape carrier, in consideration that the number of the output electrodes is larger. However, there is a technical limitation in making the outer lead pitch finer. Further, it is sometimes required to make pitch of the outer lead 12 larger depending upon the conditions of connecting to the outside. In such a case, wiring 10 must be curved when routed on the tape carrier 3, so that it becomes longer and hence the width of the TCP 1 becomes larger.
In contrast, the above Japanese Publication No. 5-326622 discloses a technique to eliminate the conventional curved pattern from the wirings on a tape carrier by arranging the electrodes on the chip at a pitch equal to that of the outer leads of the tape carrier to make the output leads of the tape carrier straight, so that the size of a TCP can be reduced. However, the problems with this prior art technique are that because the outer lead pitch decides the electrode pitch which in turn decides the size of the chip, downsizing of a chip has been difficult to achieve and the manufacturing cost of the chips has increased, and that the design flexibility of a TCP has been limited by the number and pitch of electrodes of a semiconductor chip.
Therefore, in order to eliminate the above mentioned defects and problems of the prior art, the present invention is to provide a semiconductor device comprising a semiconductor chip, for example a driver chip for driving a flat type display panel such as a LCD panel, said chip including a number of electrodes on the surface thereof, in which the mounting area can be reduced while the integration degree and size of the chip are properly balanced with its manufacturing cost.
It is another purpose of the invention to provide a tape carrier package having semiconductor chips mounted thereon, said chips including a number of electrodes as described above, in which the size and cost can be reduced while holding down the manufacturing cost of the chips.
It is also a purpose of the invention to provide a flat type display panel module which is able to reduce the size of the entire device and to substantially enlarge the display area by reducing the frame portion on which the driver semiconductor chips are mounted.